i finally got the replacement catalytic convertor and got it installed today. Although it still rattles faintly. I was wondering if anybody has had this problem with any of there catalytic convertors.

 

Congrats on the install! How rusty were the bolts for you? It might just be an exhaust hanger (check the one at the rear of the cat), or a loose heat shield somewhere.

 

if it is the hanger by the cat, HAVE FUN!!!!

That has been the biggest PITA fix i have ever done

I would rather go out back and look at my neighbors riced out Miata for hours on end than do that again thats how much fun I had

 

i rechecked the cat hanger and its not that, but i noticed that today it didnt rattle at all. Now all i have to do is find a way to get the oxygen sensor off. I tried about 20 soakings of wd-40 and a cresent wrench with a breaker bar, but that didnt work, the wrench just loosened up and slipped off. If i were to try taking it off when the car is hot, like after driving around, would that make it easier to take the sensor off?

 

There's a ton of messages up about how to remove the oxygen sensor... do a search.